Generally, image processing apparatuses, such as scanners that capture an image of a document while the document is conveyed, have a separating function for separating documents, separates a plurality of documents placed on the document tray of the apparatus and conveys the documents one by one. However, when a document folded in two etc., is conveyed, an attempt to separate the document may cause a damage on the document or a jam during the separation of the document. When a document folded in two is to be conveyed, therefore, the user makes a setting on the image processing apparatus to suspend the separating function thereof before having the document conveyed. Further, image processing apparatuses generally have an imaging device that captures an image of the front surface of the document and an imaging device that captures an image of the back surface of the document to capture the images of the front surface and the back surface of the document at once. In other words, when a document folded in two is conveyed, the image processing apparatus captures the images of the external sides of the document folded in two at once. In such a case, an image of a continuous document is captured in the two images captured by the two imaging devices, and it is preferable for the image processing device to synthesize the two images.
For example, an image processing apparatus can determine whether or not to synthesize the image captured of the front surface of the document and the image captured of the back surface of the document according to the setting made on whether or not the separating function is to be suspended. However, when thin sheets of paper, documents with a tear, perforated documents, or documents with a sticker or a photograph attached thereto are conveyed, an attempt to separate the documents may damage the document. Therefore, the image processing apparatus may have been set to suspend the separating function even when a document not folded in two is to be conveyed. An image processing apparatus that can determine appropriately whether or not to synthesize the image captured of the front surface and the image captured of the back surface is desired.
There is disclosed an image processing apparatus including a multifeed detection means for detecting a multifeed of a document by using an ultrasonic multifeed sensor and an operation means for designating an operation following the detection of a multifeed, wherein the image of the front surface and the image of the back surface of the document on which a multifeed has been detected are combined, based on the operation on the operation means (see Japanese Unexamined Patent Publication (Kokai) No. 2017-208627).
There is disclosed an image reading apparatus wherein an image captured of the front surface of the document and an image captured of the back surface of the document are combined to form one image when the apparatus is set at a large-sized sheet reading mode and it has been determined that the document conveyed is folded in half, based on the result of the reception by an ultrasonic receiver (see Japanese Unexamined Patent Publication (Kokai) No. 2010-154112).
There is disclosed a reading apparatus that, upon receiving an instruction to read both sides of a document folded in two, synthesizes the images of the both sides to form one image (see Japanese Unexamined Patent Publication (Kokai) No. 2016-127330).